What causes pine wilt?


What causes pine wilt?


Pine wilt is a common disease that causes browning and death of pines, especially Scotch pine. Austrian, mugo, red, jack, and white pine may also be affected, but less commonly than Scotch pine. Affected trees turn brown and die within a few months.

Pine wilt is caused by the pinewood nematode, a microscopic worm. The nematodes clog the water-conducting vessels of the pine tree, causing the tree to wilt and die. It spreads from tree to tree by pine sawyer beetles. Infected, dying trees are often attacked by secondary bark beetles, which leave small holes in the trunk and carry a fungus that causes blue staining of the wood, often visible as blue radial wedges when the trunk is cut in cross-section.

Unfortunately, there is no cure for pine wilt. Dying trees should be cut down and destroyed.

For more information see the encyclopedia article on Pine wilt


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